Tumbler lock



Patented Oct. 16, 1923.

PATENT QFFICE.

HAROLD CHARLTON, OI` CHICAGO, ILLINOIS.

TUMBLER LOCK.

Application filed February 20, 1922. Serial No. 537,785.

To all whom z't may concern:

Be it known that I, HAROLD CHARLTON, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Tumbler Locks, of which the following is a specification.

This invention relates to keypperated locks provided with control devices of the l0 general class known as tumblers and has for its object the provision of locks of this nature which shall be of improved construction and operation.

The invention is exemplified in the combination and arrangement of parts shown in the accompanying drawing and described in the following specification, and it is more particularly pointed out in the appended claims.

In the drawing- Fig. 1 is a longitudinal section of a lock housing showing one embodiment of the present invention;

Fig. 2 is a section on line 2-2 of Fig. 1;

Fig. 3 is a section on line 3-3 of Fig. 1; and

Fig. 4 is a perspective of one of the tumblers of the lock.

In the figures of the drawing, the numeral 10 designates a lock housing provided with a rotary barrel 11. The barrel may be held in place by any suitable means, such as a plate 12, and in the embodiment illustrated the plate 12 is provided with lugs 13 for operating a bolt or other holding device. It will be understood by those skilled in the art that the principles of the invention are not confined to any specific form of lock, but may be applied to a great variety of locks other than that shown in the drawing.

rlhe barrel 1l. has a central slot or opening 14 passing entirely through the barrel transversely of the axis thereof and extending for a sufficient distance lengthwise of the barrel to provide for a plurality of tumblers and to give the requisite length of the barrel. The opening 14 may be divided transversely by partitions or walls 15, thus form ing cells or chamber 16 for the bar tum blers 17 which constitute a characteristic feature of the present invention. The tumblers 17, as shown in Fig. 4, are made in the form of short bar sections of considerable thickness. Tumblers approximately oneeighth of an inch thick have been found to operate satisfactorily.

The housing 10 for the barrel 11 is provided with a longitudinally extending groove 18 formed in the inner wall of the housing at the lower side thereof and a corresponding groove 19 is formed diametrically opposite the groove 18. Vhen the key is removed from the lock therlower ends of the tumblers 17 drop into the groove 18 and prevent rotation of the barrel 11.

The tumblers 17 are all provided with key openings 2O for receiving the key 21. The contour of the key is so arranged that when the key is in place the tumblers will all be lifted from the groove 18 and the ends of the tumblers will be flush with the periphery of the barrel so that the barrel may be readily turned by the key. The openings 2O are staggered with relation to one another when the key is in place so that the key may not be withdrawn until the barrel is turned so that the ends of the plungers are in alinement with the grooves 18 and 19. When the barrel is in this position the plungers are free to shift back and forth to permit the various projections on the key to pass. Both edges of the key are given an irregular configuration so that the plungers are positively moved in both directions as the key is moved into and out of position in the lock. It is apparent that in order for the key to be effective the bearing between the plunger and the key should approximate a line bearing so that a particular projection will have to be accurately placed on the key in order to hold the corresponding plunger in proper` position to permit rotation of the barrel when the key is in place. To permit of the plunger of considera-ble thickness and at the same time provide this restricted bearing between the plunger and key, each plunger is longitudinally slotted, as shown at 9.2. This leaves a comparatively thin connecting wall 28 which provides bearing surfaces for the key, while at the same time the tumbler is given suflicient weight to insure action at all times.

Where tumblers are made of thin sheets their weight is not suliicient to insure positive action and any foreign substance which enters the lock may cause thin sheet tumblers to stick so that they will not drop into place when the key is removed, thus leaving the barrel free to be turned Without the use of a key. Tumblers constructed according to the present invention are of suliicient Weight to insure their action at all tiines and yet the bearings are narrow and require accurate y fitted. keys for their operation.

I claim l. A look tumbler comprising a relatively thick body member having a key opening ex tending transversely thereoi and having' :l slot in one side thereof' extending the full length of said body member to reduce the thickness of said body member to i'orin a relatively thin key bearing portion at one side of said tumbler.

2. A lock comprising a casing having a barrel rotatably mounted therein and provided with transverse openings separated 'from one another by partition Walls and tumblers arranged in said openings, said. tinnblers having slots formed therein and extending the full length thereof to provide relatively thin key bearing portions at one side of the center line of each tumbler.

3. A tumbler lock comprising a barrel having a ke opening extending longitudinally ther-eo and having transverse tumbler openings therein and tumblers arranged in said openings comprising relatively thick body portions having key openings extending' transversely therethrough in alinenient with the key openings in said barrel and having slots extending the full' length thereot to reduce the thickness of .said tumblers adjacent the key openings thus providing thin key bearing portions at one side of the center lines of the tumblers.

In testimony whereof I have signed my name to this specification 0n this 18th day of February, A. D. 1922.

HAROLD CHARLTON. 

